Laptops with Solid-State Drives: Pros and Cons

With Apple's sexy MacBook Air thrusting them into the limelight, laptops with built-in solid state drives (SSDs) are suddenly all the rage. Now they are also available from a variety of Windows OEMs including Lenovo, Toshiba and Dell. While the drives can offer higher performance than conventional rotating storage, they also add about $500- $800 to the base purchase price of laptops, and can be almost ten times as expensive as a standard hard disk.

What are some of the things to consider in buying an SSD-capable laptop, and are there situations where you would better off with the conventional hard disk-equipped models?

First, let's look at the typical configurations that are currently available. Many manufacturers offer SSDs with (at the bottom end) 32 GB of storage, which can be limiting if you need the space for videos, photographs, or a large email archive. Toshiba sells its laptop with 128 GB SSD, the same price that it earlier offered a model with half that capacity. Dell sells a laptop that starts around $1,500, while the others have configurations that are at least $2,500. Dell also has the widest selection of SSD-capable models: two lines (Latitude and Precision Workstation) and multiple models (at least at this writing) of each.

What about the need for speed? Are the SSDs faster than conventional disks?

For the most part, yes. Dell claims that its SSD can improve Latitude D430 performance up to 23 percent and can reduce boot time by up to 34 percent. Other analysts have seen similar results, because you don't have to wait for the drive to spin up or for the rotors to seek the specific place on the platter to read the data.

Apparent drive speed is made up of several factors: access time, or the time it takes for the disk to locate the data stored on the surface, and transfer rates, or how fast the information can move through the various electronics and bus connectors to the central processing unit of the PC itself.

But speed isn't the only criterion. What about how much power is used by the SSD, and what it will do to the overall battery life of the laptop?

Before you can make any definitive conclusions, you have to look at more than just the SSD itself. "You need to know what chips and technologies are being used inside the SSD along with what kind of data connection is being used between the SSD and the overall PC itself," says Brian Beard, the flash marketing manager at Samsung.

Beard talks about two factors that can swing SSD-based laptops to either save or consume more power. "First, you have to examine the disk controller used in the laptop," he says. Thinner and older laptops  such as the MacBook Air and the older Dell 430 models -- make use of a parallel ATA interface, which uses electronics that can consume more energy and degrade battery life. "The newer laptops use SATA-2 interfaces, which use half the power of the parallel ATA interfaces," he says.